One printing press can print the first edition of a book in 55 min, whereas a second printing press requires 66 min to print the same number of copies. How long would it take to print the first edition with both presses operating?
2007-04-10 04:29:36 · 4 answers · asked by noggle4 2 in Science & Mathematics ➔ Mathematics
x/66 + x/55 = 1
55x + 66x = 55•66
121x = 5•11•6•11
x = 30 min.
2007-04-10 04:43:24 · answer #1 · answered by Philo 7 · 0⤊ 0⤋
The first printing press can print 1/55th of the 1st edition in 1 minute, while the second printing press can print 1/66th of the book in 1 minute. Hence both of them can print (1/55+1/66) = (6/330+5/330) = 11/330 = 1/30th of the book in one minute. It would therefore take 30 minutes to print the whole thing.
2007-04-10 11:47:05 · answer #2 · answered by Kyrix 6 · 0⤊ 0⤋
press 1: 55 min to print x books : v1 = x/55
press 2: 66 min to print x books : v2 = x/66
If the 2 presses operate printing half the books in each press then
t1 = (x/2) / v1 => t1 = (x/2)/(x/55) = 55/2 min
t2 = (x/2)/ v2 => t2 = (x/2) / (x/66) = 66/2 min
total time = t1 + t2 = 55/2 + 66/2 = 60.5 minutes
2007-04-10 11:45:34 · answer #3 · answered by Anonymous · 0⤊ 0⤋
Well, as a printer...that would depend on the ability of the operator to run a press at a higher speed, what kind of paper (glossy is always a pain), what kind of inks (rubber or oil based)...what kind of press (AB Dick? Heidelburg?)....but seriously, I gave up doing number-word problems when I graduated. I hate these things.
2007-04-10 11:42:50 · answer #4 · answered by Blue Oyster Kel 7 · 0⤊ 0⤋